HDU 5023 a segment upt mayor's performance art (segment tree Interval Update)

Question link: http://acm.hdu.edu.cn/showproblem.php? PID = 1, 5023

Solution report: the length of a wall is N and there are n units. Each unit number ranges from 1 to n. The initial color of the wall is 2. There are 30 colors in total, there are two operations:

P a B c: color the ranges A to B to C.

Q a B: query the color from A to B

The interval of the Line Segment tree is updated. The information stored on each node includes C and 30 colors that store the color, which can be compressed to an int type for storage. Then there is a tot, the total number of colors in the interval.

For the P operation, search for the interval to be updated, and find the interval to be updated. If there is only one color for the current interval, then we need to press the information of this interval to the two subnodes of this node,

Then, select the range in which the interval to be updated is located and continue to update.

For the Q operation, this can be done at will. The information of the anyway interval exists in C of each node, as long as it is obtained according to the rule.

  1 #include<cstdio>  2 #include<cstring>  3 #include<iostream>  4 #include<algorithm>  5 using namespace std;  6 const int maxn = 1000005;  7 struct node  8 {  9     int l,r,c,tot; 10     void Node(int l1,int r1,int c1,int tot1) 11     { 12         l = l1,r = r1,c = c1,tot = tot1; 13     } 14 }tree[4*maxn]; 15 int ans; 16  17 void Init(int p) 18 { 19     if(tree[p].l == tree[p].r) return ; 20     int mid = (tree[p].l + tree[p].r) / 2; 21     tree[2*p].Node(tree[p].l,mid,2,1); 22     tree[2*p+1].Node(mid+1,tree[p].r,2,1); 23     Init(2*p); 24     Init(2*p+1); 25 } 26 void paint(int p,int l,int r,int c) 27 { 28     if(tree[p].l == l && tree[p].r == r) 29     { 30         tree[p].c = 1 << (c-1); 31         tree[p].tot = 1; 32         return ; 33     } 34     int mid = (tree[p].l + tree[p].r) / 2; 35     int T; 36     if(tree[p].tot == 1)   //如果这个节点只有一种颜色，需要先往下推  37     { 38         T = 0; 39         for(int i = 0;i < 30;++i) 40         if(tree[p].c & (1 << i)) 41         { 42             T = i+1; 43             break; 44         } 45         paint(2*p,tree[p].l,mid,T); 46         paint(2*p+1,mid+1,tree[p].r,T); 47     } 48     if(r <= mid) 49     { 50         paint(2*p,l,r,c); 51     } 52     if(l <= mid && r > mid) 53     { 54         paint(2*p,l,mid,c); 55         paint(2*p+1,mid+1,r,c); 56     } 57     else if(l > mid) 58     { 59         paint(2*p+1,l,r,c); 60     } 61     tree[p].c = tree[2*p].c | tree[2*p+1].c;   //回溯  62     int tt = 0; 63     for(int i = 0;i < 30;++i) 64     if(tree[p].c & (1 << i)) 65     tt++; 66     tree[p].tot = tt; 67 } 68 void query(int p,int l,int r) 69 { 70     if((tree[p].l == l && tree[p].r == r) || tree[p].tot == 1) 71     { 72         ans |= tree[p].c; 73         return ; 74     } 75     int mid = (tree[p].l + tree[p].r) / 2; 76     if(r <= mid) query(2*p,l,r); 77     else if(l <= mid && r > mid) 78     { 79         query(2*p,l,mid); 80         query(2*p+1,mid+1,r); 81     } 82     else if(l > mid) query(2*p+1,l,r); 83 } 84 int main() 85 { 86 //    freopen("in.txt","r",stdin); 87 //    freopen("out.txt","w",stdout); 88     int n,m; 89     while(scanf("%d%d",&n,&m),n+m) 90     { 91         tree[1].Node(1,n,2,1); 92         Init(1);     93         int a,b,c; 94         char oper[5]; 95         while(m--) 96         { 97             scanf("%s%d%d",oper,&a,&b); 98             if(oper[0] == ‘P‘) 99             {100                 scanf("%d",&c);101                 paint(1,a,b,c);102             }103             else104             {105                 ans = 0;106                 query(1,a,b);107                 int flag = 1;108                 for(int i = 0;i < 30;++i)109                 if(ans & (1 << i))110                 {111                     printf(flag? "%d":" %d",i+1); 112                     flag = 0;113                 }114                 puts("");115             }116         //    for(int i = 1;i <= 9;++i)117         //    printf(i == 9? "%d\n":"%d ",tree[i].c);118         //    for(int i = 1;i <= 9;++i)119         //    printf(i == 9? "%d\n":"%d ",tree[i].tot);120         }121     }122 }

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HDU 5023 a segment upt mayor's performance art (segment tree Interval Update)